The present invention relates to physical exercise equipment, in particular to a novel apparatus for strength training.
Many studies indicate that the isokinetic strength training technique which requires movement at constant speed and at peak force throughout the full range of motion is the most effective for building strength and muscle mass. Hydraulic cylinders are commonly used in this type of exercise equipment; since its generated resistance increases with increasing speed, it can provide to the user the resistance up to his maximum capacity and limit his motion to the speed determined by his peak force. An electric generator having an electrical resistive load connected across its two output terminals can also be used as a means for generating resistance in isokinetic exercise equipments. When the rotation speed increases, the output voltage and current raise and cause the resisting force to match the user's maximum capacity. As a result, the motion speed is limited by the user's strength. By changing the electrical resistive load, the user can change the speed limit of his motion.
The isokinetic exercise equipments which utilize hydraulic cylinder and electric generator as means for generating resistance suffer a major draw-back: lack of resistance at the beginning and the end of each motion. The resistance generated by these devices increases with increasing speed of motion; therefore, at the beginning and the end of each exercise repetition where the motion speed is minimal, the resistance is virtually diminished. As a result, the exercise motion does not have the pre-stretch and full range resistance which are necessary for an effective strength training. The present invention provides a solution for the above short-coming.